We plan to develop a direct immunoperoxidase staining procedure for the Legionnairies Disease Bacterium (LDB). The stain will be evaluated as a diagnostic technique to be used on patient sputum smears and applied to formalin-fixed lung sections in a retrospective epidemiological study and in post-mortem diagnosis of disease. Anti-LDB will be produced in goats, rabbits, and possibly other animal species. Also, antibodies will be produced in hyper-immune mice and mouse hybridomas. The advantages of each species in the production of antibodies to LDB will be evaluated. In a later phase of this project, large quantities of antisera and/or anti-LDB-peroxidase congugate may be produced for distribution through the Center for Disease Control, if this appears feasible.